The present invention relates to a thin film transistor liquid crystal display (TFTLCD). More specially, the present invention relates to a device for an in-plane switch (IPS) TFTLCD to convert the light energy into an electrical power so as to recycle the electrical power.
With the techniques of producing displays improved day-by-day, a TFTLCD is a widely applied display for a great deal of users to see pictures and information on a screen. The working principle of the TFTLCD is to alter the alignment of a great deal of liquid crystal molecules in a liquid crystal layer by applying an electric field to change the path of the light passing through the liquid crystal layer so as to express the anti-dazzling effects shown in a TFTLCD.
According the working principle described above, it is known that the light for display is provided by a backlight source, e.g. a transmission TFTLCD, or a nature light source, e.g. a reflection TFTLCD, instead of actively emitting light by liquid crystal particles themselves.
An electrical circuit of a conventional TFTLCD is shown in FIG. 1. A thin film transistor 11 can be switched in an on/off state controlled by a scanning-line voltage Vs. When a data-line voltage Vd is applied on the electrode 131 and the electrode 132, the alignment of the liquid crystal particles 12 will be altered for further controlling the penetrating degree of the light, and changing the light intensity emitted form the backlight source 14 to an observer.
FIG. 2(a) shows a top-view structure of a conventional TFTLCD composed of a top electrode and a bottom electrode and FIG. 2(b) shows a conventional in-plane switch (IPS) structure for improving the viewing angle shown by the TFTLCD. The respective controllable region 20 shown on FIG. 2(a) and FIG. 2(b) are used to produce the anti-dazzling effect controlled by an electric field. Except for the controlled region 20, the other region which is called an uncontrollable region cannot express the anti-dazzling effect. Hence, a lot of black matrixes are often used to cover the uncontrollable region so as to prevent the light from transmitted therethrough, and increase the contrast of pixels. Therefore, it is understood that the more controllable region 20 occupies in the TFTLCD, the greater of the liquid crystal molecules can be controlled by the electric field to express the anti-dazzling effect so as to reduce the manufacturing cost. However, the conventional TFT structure exists an uncontrollable region where the liquid crystal molecules are not controlled. In addition, the electrode structure and the working principle of the electric field in the IPS shown on FIG. 2(b) are different from those of the general TFTLCD consisting of the top electrode and the bottom electrode shown on FIG. 2(a).
Furthermore, The TFTLCD is usually applied to a portable computer, e.g. a notebook, which requires a battery as the power source. Consequently, saving electric power is important for designers to fabricate the TFTLCD. Moreover, the IPS TFTLCD consumes more electrical power than the conventional TFTLCD composed of the top and bottom electrodes, because the IPS TFTLCD needs a driving voltage at least greater than 12 V.
Therefore, it is attempted by the applicant to provide a TFTLCD for recycling electric power and being widely applied in different electrical products.
It is therefore an object of the present invention to provide a TFTLCD for recycling the light energy by converting apportion of light energy through a liquid crystal layer thereby into the electrical power.
It is therefore another object of the present invention to provide an TFTLCD including a liquid crystal layer having a first region and a second region therein, a liquid crystal controlling device for controlling an anti-dazzling effect in by the first region of the liquid crystal layer, and a photoelectric converting device disposed on the second region of the liquid layer for converting a portion of light energy passing through the liquid crystal layer into electrical power thereby recycling the light energy.
Preferably, the liquid crystal layer includes a plurality of liquid crystal molecules to be filled with the crystal layer between a first insulation substrate and a second insulation substrate.
Preferably, each of the first insulation substrate and the second insulation substrate is formed of a transparent glass substrate. The first region is a controllable region for an electrical filed to control the anti-dazzling effect. The second region is an uncontrollable region for setting the photoelectric converting device thereon.
Preferably, the liquid crystal controlling device includes a pixel electrode electrically connected to a transistor for providing an electric field to control the anti-dazzling effect, a thin film transistor (TFT) being the transistor to be electrically connected with the pixel electrode for selectively being turned on and off, a common electrode electrically connected with a end of the TFT.
Preferably, the TFT further has a gate end electrically connected with a scanning-line electrode to form the electric filed. The scanning-electrode is electrically connected to the common electrode for further electrically connecting with the pixel electrode to form the electric field. Each of the pixel electrode and the common electrode is formed of a comb-shaped pixel electrode and a comb-shaped common electrode, and each of the pixel electrode and the common electrode has a respective teeth set by extending into the intervals formed between the pixel electrode and the common electrode.
Preferably, the pixel electrode has a layout in a shape corresponding to the common electrode. The pixel electrode and the common electrode are transparency electrodes. And the transparent electrodes are made of a material selected from one of indium tin oxide (ITO) and lead tin oxide.
Preferably, the liquid crystal controlling device further includes a signal electrode and a scanning-line electrode to be respectively connected to a drain end and a gate end of the TFT.
Preferably, the photoelectric converting device is for a photovoltaic battery usage, including a first electrode, a photovoltaic unit disposed on the first electrode, a doped semiconductor structure formed on the photovoltaic unit, and a second electrode formed on the doped semiconductor structure.
Preferably, the photovoltaic unit is made of an ultrathin transparency film selected from one of polysilicon and amorphous polysilicon material.
Preferably, the doped semiconductor structure is made of a heavily-doped material selected from one of a group consisting of polysilicon, P type amorphous polysilicon and N type amorphous polysilicon material.
Preferably, the first electrode and the second electrode are transparent electrodes. And the transparency electrodes are formed of a same material as that of the pixel electrode and the common electrode selected from one of indium tin oxide (ITO) and lead tin oxide.
Preferably, the first electrode and the second electrode have a layout in a shape corresponding to a combination region of the comb-shaped pixel electrode and the comb-shaped common electrode.
It is therefore a further object of the present invention to provide an in-plane switch (IPS) TFTLCD including a first insulation substrate, a second insulation substrate, a liquid crystal layer filled between the first insulation substrate and the second insulation substrate therein, a plurality of scanning-line electrodes and a plurality of signal-line electrodes formed on a surface bounded between the first insulation substrate and the liquid crystal layer, a plurality of liquid crystal controlling devices respectively formed in the common border of the scanning-line electrodes and the signal-line electrodes for controlling an anti-dazzling effect of the liquid crystal layer. And each of the liquid crystal controlling units including a thin film transistor (TFT) electrically connected with the scanning-line electrodes and the signal-line electrodes, a comb-shaped pixel electrode and a corresponding comb-shaped common electrode having a respective teeth extending into the intervals formed between the comb-shaped pixel electrode and the corresponding comb-shaped common electrode, and a photoelectric converting device disposed between the first insulation substrate and the second insulation substrate and having a layout in a shape corresponding to a combination region of the comb-shaped pixel electrode and the comb-shaped common electrode.
Preferably, the first insulation substrate and the second insulation substrate are respectively made of a transparent glass substrate.
Preferably, each of the pixel electrode and the common electrode is formed of a transparent electrode.
Preferably, the TFT has a gate end electrically connected to an end of a corresponding one of the scanning-line electrodes and a drain end electrically connected to an end of a corresponding one of the signal electrodes.